Bullet.



BULLET.

Patented June 20, 1916.

E. M. SHINKLE.

APPLICATION FILED FEB. 19, 1915.

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EDWARD 1V1. SHINKLE, OF THE UNITED STATES ARMY.

BULLET.

Application filed February 19, 1915.

To all whom it may concern:

Be it known that I, EDWARD SHINKLE, major U. S. Army, a citizen of theUnited States, residing at Philadelphia, in the county of Philadelphiaand State of Pennsylvania, have invented certain new and usefulImprovements in Bullets; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

This invention relates to bullets for re arms of all kinds, and has forits object to improve the bullet' made the subject of U. S. Patent to J.E. Bell, #807,012, December 12, 1905 for rifle bullet.

With this object in view the invention consists in the novel details ofconstruction and combinations of parts more fully hereinafter disclosedand particularly pointed out in the claims.

Referring to the accompanying drawings forming a part of thisspecification in which like numerals designate like parts in all theviews :-Figure 1 is a diagrammatic view partly in section of a bulletmade in accordance with my invention; Fig. 2 is a-sectional view on agreatly exaggerated scale of some of the parts shown in Fig. 1; and Fig.3 is a view similar to Fig. 1 showing the old style bullet illustrated'in U. 6. Patent #807,012, above mentioned.

The bullets used in military and other high velocity rifles are eithercomposite bullets consisting of a jacket of copper, cupronickel, softsteel, or other metal of considerable strength, filled with a softer andmore ductile metal such as lead or one of its alloys, or they are madeof a single metal or alloy such as copper or bronze. In either case themost customary form is a cylindrical body of a diameter approximatelyequal to the bore of the rifle measured'to the bottom of the grooves, towhich is added a point, that may be conical, ogival, or of any otherform suitable for the purpose for I which the bullet is designed.

The fact that the diameter of the bore of the rifle is approximately0.008 less when measured to the lands than when measured to the bottomof the grooves of the rifiing causes the riding to cut grooves in amanner well known in the exterior of the body of the bullet for theentire length over which Specification of Letters Patent.

latenteol June 20, 191.6.

Serial No. 9,399.

its diameter is greater than the nominal bore or the diameter measuredto the lands. While it is necessary to have some portion of the body ofa diameter approximately as great as the diameter of the bore of therifle measured to the bottom of the grooves, the length of the portionof this diameter need only be enough to impart angular velocity to thebullet and to prevent the escape of powder gases past the bullet. Anygreater length of this diameter simply requires a greater length ofmetal to be cut by the lands of the rifiing and thus increases thefriction in the bore.

Inventors and experimenters with small arms rifle bullets haverecognized the loss of efliciency of bullets of the cylindrical bodytype and have attempted .in various ways such as by the use ofcannelures filled with a lubricant,' and the use of a bullet the mainportion of the body of which is cylindrical and of the nominal diameterof the rifle, with a short cylindrical portion at the rear of greaterdiameter, to reduce the friction in the barrel. One example of suchbullets is found in the said U. S. Patent 807,012. But such a bullet hasvery serious defects as have all others known to me which will beapparent when it is remembered that: In the first place if a-bullet ofthis character is entered into the mouth of the cartridge case farenough to afford a reasonable security in handling, the front of therotating band will not come in contact with the real conical portion ofthe rifling usually known as the forcing cone. The result is that thebullet must move in a distance of say 0.25 more or less, before takingthe rifling. This is detrimental to accuracy, and in addition allows theescape of a portion of the powder gases ast the opening between thebullet and the orcing cone causing excessive erosion and loss ofeffective work of a portion of the gases from the powder charge. Againthat type of bullet having a cylindrical body of the same diameterthroughout first comes in contact with the forcing cone or conicalportion of the rifling at a point on the bullet forward of thecylindrical body. Under these conditions gas escapes past the bulletbefore it has moved forward far enough to completely seal the bore.

To remedy the objections described above my bullet is so designed as tosubstantially or completely seal the bore when forced into firingposition by the breech mechanism and has as small an amount of metal tobe cut by the lands of the rifle as will be sufiicient to seal the boreagainst the escape of powder gases as well as to impart an angularvelocity to the bullet. A suitable length for the metal to be out alongthe length of the bullet in many cases will be say 0.16645.

In order that the present invention may be clearly understood, referenceis had to the drawings in which 1 indicates the barrel of any rifle,pistol, or fire arm provided with rifling; 2 the lands of the rifling, 3the point near the rear end of the lands where the said lands begin totaper ofl to form a forcing cone, 1 the tapered or beveled surface ofthe lands, or forcing cone, 5 the extreme rear end of the lands or baseof said forcing cone, and 6 the Wall of the cartridge receiving chamber.

7 represents the cartridge casing, 8 the rear end of the bullet fittingsaid casing, 9 the body of the bullet, and 10 its forward tapered end.

The zibove features of construction are or may be of any well known orsuitable dimen sions.

In the bullet 11, made the subject of the said U. S. Patent 807012, itsrear end 12, Was made the full diameter of the bullets then in use,while its forward body portion was slightly reduced in size to fit thediameter of the bore between the lands all as is illustrated in Fig. 3.I have discovered, however, as above stated, that whereas the bullet ofsaid patent did constitute an improvement over the prior bullets, yet inpractice it is defective in the following particulars: The said fullsized rear end 12 joins the reduced fore body 11 of the bullet by arather abrupt shoulder 13, so that since the said end 12 does notnormally enter the forcing cone 4, there is left a hollow space 14-,between the wall of the forcing cone and the shoulder 13. In otherwords, although I found in actual tests that the bullet of'said patentdid reduce the friction in the gun, and therefore produced a highervelocity for a given pressure, all as disclosed in said patent, yet,said tests further showed that these results were not satisfactory, inthat the bullet of the patent is not accurate and did not otherwisefunction as efficiently as was desired. I further discovered from saidtests that these defects were due to the presence of the space 1 1between the rear end 12 and reduced fore body 11 of the bullet, whichpermits the gases of explosion to escape to a greater or less extentbefore the rear end 12 has fully taken the rifling. In the presentinvention I remedy these defects as also stated above by doing away withthe abrupt shoulder 13 altogether, and while retaining a reduced forebody 9, I so taper that portion 15 of the bullet that is to take therifling that its surface 16 will fit, or substantially fit, the surface4; of the particular forcing cone with which it is to function, all aswill be clear from Figs. 1 and 2.

The rear end 8 of my bullet of course may be of various shapes anddimensions to suit the arm it is designed for, but in the drawings Ihave illustrated it as cylindrical, and of the same diameter as the body9.

In order to give a specific example of the construction of a bullet madein accordance with this invention, it is said: The bullet shown in Figs.1 and 2 of the drawing which is not to scale is designed for use in theUnited States magazine rifle caliber .30, model of 1903, chambered formodel of 1906 ammunition, and is intended to illustrate the principlesinvolved so clearly that anyone skilled in the manufacture of small armsammunition may be able to manufacture ammunition of this design for anyother fire arm by making suitable changes in dimensions.

The cylindrical base portion 8 of this bullet is of a diameter ofsubstantially 0.2995, which is equal to or slightly greater than thenominal diameter of the rifle in which it is to be fired. The conicalsection 15 fits the forcing cone 1 of the rifle in which it is to befired. The cylindrical portion 9 is equal to or slightly greater indiameter than the nominal bore of the rifle in which it is to be fired,and extends from the conical portion 15 to the beginning of thecurvature of the pointed end 10, which can be of any shape desired. Acannelure 20 may or may not be added as desired, at the front end of thepart 8 for crimping purposes.

It is obvious that those skilled in the art may vary the details ofconstruction, as well as the arrangement of parts Without departing fromthe spirit of my inventionfor example, the dimensions appearing on thedrawings may be increased say 0.00land therefore I do not wish to belimited-to the above disclosure except as may be required by the claims.

,What I claim is 1. A bullet for use in military rifles provided with asharp nose portion; a cylindrical portion of substantially the diameterof the bore between the lands located in rear of and joining said sharpnose portion; a forwardly tapered portion located in the rear of andjoining said cylindrical portion; said tapered portion having a diameterat its front end of substantially the diameter between the lands, andhaving a diameter at its rear end of substantially the diameter of thebore between the grooves; and a second cylindrical portion in rear ofand joining said tapered portion substantially as de scribed.

2. A bullet for use in military rifles pro yided with a sharp noseportion, a cylindrical portion of the diameter of the bore between thelands located in rear of and joining said sharp nose portion; aforwardly tapered portion having a base of the diameter of the borebetween the grooves in rear of and joining said cylindrical portion;

and a second cylindrical portion of the same diameter as said firstnamed cylindrical por-

